The invention relates generally to medical devices and more particularly to side-firing optical fibers and methods for using such devices.
By using side-firing or laterally-firing optical fibers for laser-based surgical procedures, a medical practitioner can more accurately control the application of laser energy to the appropriate treatment area. Passing the distal end portion of the optical fiber through an endoscope during surgery, however, may damage, scratch, degrade, or deform the distal end portion of the optical fiber. A damaged optical-fiber end portion may reduce side-firing laser energy delivered or increase overheating during use of the device. To protect the optical-fiber end portion, a metal cap, tube, or cannula, usually made of surgical grade stainless steel, is placed over the optical fiber end. In some instances, using a protective metal cap increases the profile or size of the optical fiber end for insertion and positioning within the endoscope.
Another consideration in laser-based surgical procedures is the effect of back-scattered laser energy during treatment. When sufficient back-scattered laser energy strikes a protective metal cap, the protective metal cap can also degrade and portions can be released into the patient's body. Moreover, an overheated protective metal cap can also affect the mechanical and optical properties of those portions of the optical fiber end that are in close proximity. Cooling of the device may be needed to operate at a safe temperature.
Thus, a need exists for optical fiber end portions that can increase side-fired laser energy, increase device longevity, increase transmission efficiency, reduce overheating, and/or increase patient safety.